CA1176429A - Hnco manufacture by adiabatic air oxidation of hcn - Google Patents
Hnco manufacture by adiabatic air oxidation of hcnInfo
- Publication number
- CA1176429A CA1176429A CA000408075A CA408075A CA1176429A CA 1176429 A CA1176429 A CA 1176429A CA 000408075 A CA000408075 A CA 000408075A CA 408075 A CA408075 A CA 408075A CA 1176429 A CA1176429 A CA 1176429A
- Authority
- CA
- Canada
- Prior art keywords
- catalyst
- hydrogen cyanide
- process according
- oxygen
- reaction
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01C—AMMONIA; CYANOGEN; COMPOUNDS THEREOF
- C01C3/00—Cyanogen; Compounds thereof
- C01C3/14—Cyanic or isocyanic acid; Salts thereof
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Catalysts (AREA)
Abstract
,682 HNCO MANUFACTURE BY ADIABATIC AIR OXIDATION OF HCN
ABSTRACT OF THE DISCLOSURE
A process for the air oxidation of hydrogen cyanide to isocyanic acid in the presence of a solid catalyst utilizing adiabatic conditions and controlling temperatures by the proportion of inert gas.
ABSTRACT OF THE DISCLOSURE
A process for the air oxidation of hydrogen cyanide to isocyanic acid in the presence of a solid catalyst utilizing adiabatic conditions and controlling temperatures by the proportion of inert gas.
Description
~6~
HNCO MANUFACTURE BY ADIABATIC AIR OXIDATION OF ~ICN
This invention relates to the manufacture of isocyanic acid, HNCO, by oxidation of hydrogen cyanide gas with oxygen in contact with a solid catalyst effec-tive to promote the reaction, and in particular provides a process giving sub~tantially complete conversion of hydrogen cyanide with high yields of isocyanic acid.
The oxidation of hydrogen cyanide in gas state using a silver catalyst has long been known. (see U.S.
Patent 2,712,493 to Moje). Gold and silver-gold alloy have also been used as catalyst (see U.S. Patent 3,032,582 to Zima). The oxidation, as described in the literature, proceeds at relatively elevated temperatures i.e. 300 - 800C. The principal reactions are those favoring the production of cyanogen and isocyanic acid.
15 Water is necessarily formed, as are other by-products such as carbon monoxide and carbon dioxide. In addition solids in the form of polymers of isocyanic acid are also formed. When ~he desired product is isocyanic acid, it i~ known that at least a stoichiometric proportion of 20 oxygen must be present. (see Zima U.S. Patent 3,032,582).
An important object of the present invention is to provide a process Eor the manufacture of isocyanic acid which can be carried out at temperatures less than 7~0C while maintaining ~ubstantially complete conversion 25 of hydrogen cyanide with high selectivity for isocyanic acid. Operation with lower reaction temperature at the catalyst will ex~end the life of the catalyst.
This and other objects of the invention are obtained basically by oxidation of gaseous hydrogen ~'764Z~
cyanide with oxygen ~t temperatures on the order of 500 - 700 utilizing a solid heterogeneous contact cat-alyst effective to promote the oxidation of hydrogen cyanide to isocyanic acid in which the process is carried out adiabatically utilizin~ a sufficient amount of inert gas in the reactan~ feed mixture to regulate and maintain a steady reaction temperature wi~hout need for external cooling means.
The oxygen supplied in the reaction feed mix-ture should be equal to or in excess of that requiredstoichiometrically for the reaction:
HCN ~ 1/2 2 = HCNO
Preferably the molar ratio of oxygen to hydrogen cyanide ln the reaction feed mixture is between 0.5 and 0.7.
The inert gas utili~ed to control temperature is preferably nitrogen. Other gases inert under the reaction condi~ions are also sui~able. The total re-quirements of inert gas for adiabatic operation will vary depending on the reactor construction, the catalyst utilized and the operating tempera~ure desired. Usually, the nitrogen requirement for adiabatic operation of the process, expressed on a molar basis with respect to the hydrogen cyanide, (including any nitrogen supplied with air when the oxygen supply is air) will be about 9 to 16 moles nitrogen per mole of HCN.
Catalyst contact time is usually about 10 to 100 milliseconds. The reaction is carried out normally at or sligh~ly above atmospheric pressure. Pressure, however, is not critical, and lower and higher pressures can be used. It is an advantage of the process that it can be operaeed without high pressures which would in crease the danger of hydrogen cyanide leakage from ~he equipment.
Metal catalysts, particularly silver or gold or mixtures of both are preferred. The metal catalyst can be in the form of wire, such as gauze or chopped wire !
granules or silver crystals. Silver crystals are the ~76~Z~
most preferred catalyst. A particularly desirable cata lyst is silver crystals doped with palladium, as described in Fei~, Kilanows~i and Olson, application Serial No.
~ 5 , iled concurrently herewith. The doped catalyst permits operation at substantially lower temper-atures than can be obtained using silver crystals alone~
As used herein the word adiabatic defines an operation in which heat is neither added to nor extracted from the reaction mixture by external means. The heat of reaction is e~sentially all removed by the gas stream traversing the reactor. Adiabatic operation of the HC~
oxidation is particularly advantageous since glass or ccramic reactors are preferred, and it would be difficult to remove hea~ through glass or ceramic walls. Steel reactors, or example, are generally undesirable since the steel may have an unwanted catalytic effect on the reac-tion, tending to produce excess by-products, particularly carbon monoxide and carbon dioxide. It is contemplated within the scope of the invention, however, that the walls of the re~ctor may have to be cooled only to the extent necessary to prevent damage when steel reactor~ are em-ployed. Only a small proportion (e.g. 10%) of the heat of reaction would be removed by such cooling.
An important aspect of this invention is con-trol of the reaction temperature essentially by adjusting the concentration of inert gas in the reactant feed mix-ture. It is contemplated that operation of the reaction will be carried out continuously under adiabatic con-ditions over extended periods of time. It is necessary during a short perio~ at start-up to add heat in order to ignite the reaction which then continues adiabatically.
Any suitable method of preheating the catalyst bed to near the ignition temperature can be used. It is important, however, to avoid temperature excursions near the 960C
melting point oE silver To avoid this, the concentration of either one or both o~ the reactants, hydrogen cyanide and oxygen, may gradually be increased to the design ~76 ~
concentration in order to control the catalyst bed temper-ature within prescribed limits during start-up. After the reaction becomes spon~aneous and the desired reactant ratio for continuous operation is reached, the reaction temperature at the catalyst reaction zone is controlled during the continuous operation essentially by adjusting the amount of inert gas in the feed mixture.
EXAMPLES
In each of the following tabulated examples a catalyst in the amount of 50 grams was charged to a glass-lined reactor forming a 40 millimeter diameter by 13 millimeter high bed supported on quartz chips. A gaseous mixture o~ hydrogen cyanide, air and nitrogen was fed to the bed in each example at a flow rate, an oxygen to hydrogen cyanide molar ratio and a nitrogen to hydrogen cyanide molar ratio as indicated in Tables I, II and III
for the respective runs. The Tables also show the con-ditions and results for each run in terms of reaction temperature, conversion based on hydrogen cyanide feed and the HNCO yield. -~he hydrogen cyanide in the feed co~tained 0.02~ sulfur dioxide, as a vapor phase polymer-ization inhibitor.
The reactor start-up procedure was as follows:
Initially the reactor and a preheat zone through which the feed stream was passed were heated electrically to 450 -600C with nitrogen flow at about the design rate and with air at about 40% of the design rate. Hydrogen cyanlde flow was then started at the design rate and the electrical heaters were turned of. The catalyst bed temperature continued to rise 100 to 150C as a result of the reaction exother~. This was followed by a tempera~ure decrease, as the temperature dropped in the reactor preheat zone. At that point the air flow rate was increased in increments to the design rate to keep the reaction zone temperature near the target level. At tbe steady state (with no pre-heating of the mixed gas feed), final adiustment of the reaction temperature was made by adjusting the flow rate ~7fi~
of the nitrogen diluent.
The data in the Tables were obtained at steady state adiabatic operation after the above descri~ed start-up procedure.
S Table I describes a series of Examples I - ~VII
utilizing a silver catalyst charge which was prepared by conventional electrolysis of an aqueous solution of a suitable silver salt. The purity of the silver was on the order of 99.9%, and the crystals were in needle form with varying particle size. The particular catalyst was designated as 8 x 30 mesh, a proprietary designation indicating particles 0.6 to 2.0 mm thick~
Table II describes a series of Examples XVIII -XXIII utilizing 8 x 30 mesh silver crystals, as a cata-I5 lys~, which had been coated with palladium to a bulk con-centration of 200 ppm, as described in the above noted Feit, Kilanowski and Olson application.
Table III describes a series of Examples XXIV -XXVIII utilizing 8 x 30 mesh silver crystals, as a cata-lyst, which had been coated with palladium to a bulk con-centration of 2000 ppm, as described in the Feit, Kilanowski and Qlson application.
In each Table the Examples have been arranged in order of ascending reaction tempera~ure. Temperatures were measured by a thermocouple attached to the reactor wall adjacent to the catalyst bed.
In all of the Examples the reaction pressure was about 16 psia and the catalyst contact times were be-tween 19 and 36 milliseconds.
Examples I - IV represented the lowest temper-atures which could be maintained with the particular reaction and catalyst. As can be seen by reference to Tables II and III, substantially lower temperatures could be maintained with the palladlum on silver catalyst.
64~
o ~ o ~o . o~ ~ .
u~ o ~ ~ ~ ~ o ~D 0~00 Ln ~ ~ Y~ ~ o o~ ~` ~o~
E--~ u-~ o d cr~ 1 f) ~
~ C~l .
~: O 0 V ~ . ~ . . ~J~
~0 ~0~ . ~ - - -~C ~ ~ ~ o ~ C~l ~t:
_~
~ S
E~ ~ o~ ~ oo~
O ~ ~ ~ 0 ~ 0~ o o ~ -x ~o ~u~ ~ ~
~ ~ o~o~ ~ou~ooo o o `J u~ oo ~ o ,, ~ ~D U~ O ~ o~ ~ o ~ O~
O ~ O ~ ~ ~ C`l o ~ ~ z æ o r~ ~ cn . o ,~
6 CL o ~ ~`tV E; ~ z; O C:) O
3 E~ z u~ :i; u7 C.~ C~
- \
7~
_ 1 7 1 _ O
~ ~ o ~ o ~ ~ ~ ~ X ~
~~ ~ ~
U~ L\ O
C~
O o ~ , ~ G .
C
vb ~ r~ P
~:
~ Ct~ ~ o o~
Vl X ~ ~ O~ ~ o~
~ ~ ~0 G~ a~
~ ~: o l~o~D`5 6 ~
e ~x `
~:
:r: ~ o ~ ~o ~ ~
o X ~ U~
~a o - -r~r--o O
o~ ~ o o o~_I
O
~ ~o~ ~
o ~ ~
~J ~
X o~ o a~ O
U~
1~ ~ O
o t~O o ~
Z C~ Z O ~ ~ O~-~ ^ O O
.6 Ei æ, ,~1 Q X ~ o "~ ~; O O ~
~76~
' 8 O ~cr~
u~ o ~D ~ 0 ~ , ~ ~ o X ~o o ~ ~ ~
CO
~ O CJ~ 1--o ~
C`l U~ . . . _, ~ ~D O ~ a~
X ~o~
~ o P~ X ~.D `D o o cr~
O u~O ~ 0 + X ~ o~
~ l ~ .
. E~
o ~ ~ r~
X U~O ~ o~O~
X ~ o ~ cr~
oc ~:
oo ~ o~ ~ o ..
Z V ~ ~ o ~ ~ Z ~ Z 0 V O ;~ ~_ Z O O O ~J
X 6 z o O z 3~ 3~
~ ~76 ~9 ;9 . . .~C~I~O
~ o x o o~
. ... I~ O
'n ~ o ~ cr~
~: X ~o P~ X
g U~
o o o ~o ~: ~ ~ u~ O O ~ a~
~ ~U~ ~
~ x E~
U~
~ o C~ C~ ~ 0~ ~ C`l ~o ~ ~ o o o o~ ~ . . .
~ O
X U~
~,oCO .
o 1, ~ ~ u Z
~ ~ ~Z z O ~ ~ ~n ou o a C ~.u 0~
Cl~ :Z o ~ o ~) 6 ~ ~O zi ~ 3 X aJ C) o o Z cn
HNCO MANUFACTURE BY ADIABATIC AIR OXIDATION OF ~ICN
This invention relates to the manufacture of isocyanic acid, HNCO, by oxidation of hydrogen cyanide gas with oxygen in contact with a solid catalyst effec-tive to promote the reaction, and in particular provides a process giving sub~tantially complete conversion of hydrogen cyanide with high yields of isocyanic acid.
The oxidation of hydrogen cyanide in gas state using a silver catalyst has long been known. (see U.S.
Patent 2,712,493 to Moje). Gold and silver-gold alloy have also been used as catalyst (see U.S. Patent 3,032,582 to Zima). The oxidation, as described in the literature, proceeds at relatively elevated temperatures i.e. 300 - 800C. The principal reactions are those favoring the production of cyanogen and isocyanic acid.
15 Water is necessarily formed, as are other by-products such as carbon monoxide and carbon dioxide. In addition solids in the form of polymers of isocyanic acid are also formed. When ~he desired product is isocyanic acid, it i~ known that at least a stoichiometric proportion of 20 oxygen must be present. (see Zima U.S. Patent 3,032,582).
An important object of the present invention is to provide a process Eor the manufacture of isocyanic acid which can be carried out at temperatures less than 7~0C while maintaining ~ubstantially complete conversion 25 of hydrogen cyanide with high selectivity for isocyanic acid. Operation with lower reaction temperature at the catalyst will ex~end the life of the catalyst.
This and other objects of the invention are obtained basically by oxidation of gaseous hydrogen ~'764Z~
cyanide with oxygen ~t temperatures on the order of 500 - 700 utilizing a solid heterogeneous contact cat-alyst effective to promote the oxidation of hydrogen cyanide to isocyanic acid in which the process is carried out adiabatically utilizin~ a sufficient amount of inert gas in the reactan~ feed mixture to regulate and maintain a steady reaction temperature wi~hout need for external cooling means.
The oxygen supplied in the reaction feed mix-ture should be equal to or in excess of that requiredstoichiometrically for the reaction:
HCN ~ 1/2 2 = HCNO
Preferably the molar ratio of oxygen to hydrogen cyanide ln the reaction feed mixture is between 0.5 and 0.7.
The inert gas utili~ed to control temperature is preferably nitrogen. Other gases inert under the reaction condi~ions are also sui~able. The total re-quirements of inert gas for adiabatic operation will vary depending on the reactor construction, the catalyst utilized and the operating tempera~ure desired. Usually, the nitrogen requirement for adiabatic operation of the process, expressed on a molar basis with respect to the hydrogen cyanide, (including any nitrogen supplied with air when the oxygen supply is air) will be about 9 to 16 moles nitrogen per mole of HCN.
Catalyst contact time is usually about 10 to 100 milliseconds. The reaction is carried out normally at or sligh~ly above atmospheric pressure. Pressure, however, is not critical, and lower and higher pressures can be used. It is an advantage of the process that it can be operaeed without high pressures which would in crease the danger of hydrogen cyanide leakage from ~he equipment.
Metal catalysts, particularly silver or gold or mixtures of both are preferred. The metal catalyst can be in the form of wire, such as gauze or chopped wire !
granules or silver crystals. Silver crystals are the ~76~Z~
most preferred catalyst. A particularly desirable cata lyst is silver crystals doped with palladium, as described in Fei~, Kilanows~i and Olson, application Serial No.
~ 5 , iled concurrently herewith. The doped catalyst permits operation at substantially lower temper-atures than can be obtained using silver crystals alone~
As used herein the word adiabatic defines an operation in which heat is neither added to nor extracted from the reaction mixture by external means. The heat of reaction is e~sentially all removed by the gas stream traversing the reactor. Adiabatic operation of the HC~
oxidation is particularly advantageous since glass or ccramic reactors are preferred, and it would be difficult to remove hea~ through glass or ceramic walls. Steel reactors, or example, are generally undesirable since the steel may have an unwanted catalytic effect on the reac-tion, tending to produce excess by-products, particularly carbon monoxide and carbon dioxide. It is contemplated within the scope of the invention, however, that the walls of the re~ctor may have to be cooled only to the extent necessary to prevent damage when steel reactor~ are em-ployed. Only a small proportion (e.g. 10%) of the heat of reaction would be removed by such cooling.
An important aspect of this invention is con-trol of the reaction temperature essentially by adjusting the concentration of inert gas in the reactant feed mix-ture. It is contemplated that operation of the reaction will be carried out continuously under adiabatic con-ditions over extended periods of time. It is necessary during a short perio~ at start-up to add heat in order to ignite the reaction which then continues adiabatically.
Any suitable method of preheating the catalyst bed to near the ignition temperature can be used. It is important, however, to avoid temperature excursions near the 960C
melting point oE silver To avoid this, the concentration of either one or both o~ the reactants, hydrogen cyanide and oxygen, may gradually be increased to the design ~76 ~
concentration in order to control the catalyst bed temper-ature within prescribed limits during start-up. After the reaction becomes spon~aneous and the desired reactant ratio for continuous operation is reached, the reaction temperature at the catalyst reaction zone is controlled during the continuous operation essentially by adjusting the amount of inert gas in the feed mixture.
EXAMPLES
In each of the following tabulated examples a catalyst in the amount of 50 grams was charged to a glass-lined reactor forming a 40 millimeter diameter by 13 millimeter high bed supported on quartz chips. A gaseous mixture o~ hydrogen cyanide, air and nitrogen was fed to the bed in each example at a flow rate, an oxygen to hydrogen cyanide molar ratio and a nitrogen to hydrogen cyanide molar ratio as indicated in Tables I, II and III
for the respective runs. The Tables also show the con-ditions and results for each run in terms of reaction temperature, conversion based on hydrogen cyanide feed and the HNCO yield. -~he hydrogen cyanide in the feed co~tained 0.02~ sulfur dioxide, as a vapor phase polymer-ization inhibitor.
The reactor start-up procedure was as follows:
Initially the reactor and a preheat zone through which the feed stream was passed were heated electrically to 450 -600C with nitrogen flow at about the design rate and with air at about 40% of the design rate. Hydrogen cyanlde flow was then started at the design rate and the electrical heaters were turned of. The catalyst bed temperature continued to rise 100 to 150C as a result of the reaction exother~. This was followed by a tempera~ure decrease, as the temperature dropped in the reactor preheat zone. At that point the air flow rate was increased in increments to the design rate to keep the reaction zone temperature near the target level. At tbe steady state (with no pre-heating of the mixed gas feed), final adiustment of the reaction temperature was made by adjusting the flow rate ~7fi~
of the nitrogen diluent.
The data in the Tables were obtained at steady state adiabatic operation after the above descri~ed start-up procedure.
S Table I describes a series of Examples I - ~VII
utilizing a silver catalyst charge which was prepared by conventional electrolysis of an aqueous solution of a suitable silver salt. The purity of the silver was on the order of 99.9%, and the crystals were in needle form with varying particle size. The particular catalyst was designated as 8 x 30 mesh, a proprietary designation indicating particles 0.6 to 2.0 mm thick~
Table II describes a series of Examples XVIII -XXIII utilizing 8 x 30 mesh silver crystals, as a cata-I5 lys~, which had been coated with palladium to a bulk con-centration of 200 ppm, as described in the above noted Feit, Kilanowski and Olson application.
Table III describes a series of Examples XXIV -XXVIII utilizing 8 x 30 mesh silver crystals, as a cata-lyst, which had been coated with palladium to a bulk con-centration of 2000 ppm, as described in the Feit, Kilanowski and Qlson application.
In each Table the Examples have been arranged in order of ascending reaction tempera~ure. Temperatures were measured by a thermocouple attached to the reactor wall adjacent to the catalyst bed.
In all of the Examples the reaction pressure was about 16 psia and the catalyst contact times were be-tween 19 and 36 milliseconds.
Examples I - IV represented the lowest temper-atures which could be maintained with the particular reaction and catalyst. As can be seen by reference to Tables II and III, substantially lower temperatures could be maintained with the palladlum on silver catalyst.
64~
o ~ o ~o . o~ ~ .
u~ o ~ ~ ~ ~ o ~D 0~00 Ln ~ ~ Y~ ~ o o~ ~` ~o~
E--~ u-~ o d cr~ 1 f) ~
~ C~l .
~: O 0 V ~ . ~ . . ~J~
~0 ~0~ . ~ - - -~C ~ ~ ~ o ~ C~l ~t:
_~
~ S
E~ ~ o~ ~ oo~
O ~ ~ ~ 0 ~ 0~ o o ~ -x ~o ~u~ ~ ~
~ ~ o~o~ ~ou~ooo o o `J u~ oo ~ o ,, ~ ~D U~ O ~ o~ ~ o ~ O~
O ~ O ~ ~ ~ C`l o ~ ~ z æ o r~ ~ cn . o ,~
6 CL o ~ ~`tV E; ~ z; O C:) O
3 E~ z u~ :i; u7 C.~ C~
- \
7~
_ 1 7 1 _ O
~ ~ o ~ o ~ ~ ~ ~ X ~
~~ ~ ~
U~ L\ O
C~
O o ~ , ~ G .
C
vb ~ r~ P
~:
~ Ct~ ~ o o~
Vl X ~ ~ O~ ~ o~
~ ~ ~0 G~ a~
~ ~: o l~o~D`5 6 ~
e ~x `
~:
:r: ~ o ~ ~o ~ ~
o X ~ U~
~a o - -r~r--o O
o~ ~ o o o~_I
O
~ ~o~ ~
o ~ ~
~J ~
X o~ o a~ O
U~
1~ ~ O
o t~O o ~
Z C~ Z O ~ ~ O~-~ ^ O O
.6 Ei æ, ,~1 Q X ~ o "~ ~; O O ~
~76~
' 8 O ~cr~
u~ o ~D ~ 0 ~ , ~ ~ o X ~o o ~ ~ ~
CO
~ O CJ~ 1--o ~
C`l U~ . . . _, ~ ~D O ~ a~
X ~o~
~ o P~ X ~.D `D o o cr~
O u~O ~ 0 + X ~ o~
~ l ~ .
. E~
o ~ ~ r~
X U~O ~ o~O~
X ~ o ~ cr~
oc ~:
oo ~ o~ ~ o ..
Z V ~ ~ o ~ ~ Z ~ Z 0 V O ;~ ~_ Z O O O ~J
X 6 z o O z 3~ 3~
~ ~76 ~9 ;9 . . .~C~I~O
~ o x o o~
. ... I~ O
'n ~ o ~ cr~
~: X ~o P~ X
g U~
o o o ~o ~: ~ ~ u~ O O ~ a~
~ ~U~ ~
~ x E~
U~
~ o C~ C~ ~ 0~ ~ C`l ~o ~ ~ o o o o~ ~ . . .
~ O
X U~
~,oCO .
o 1, ~ ~ u Z
~ ~ ~Z z O ~ ~ ~n ou o a C ~.u 0~
Cl~ :Z o ~ o ~) 6 ~ ~O zi ~ 3 X aJ C) o o Z cn
Claims (8)
1. A process for oxidation of hydrogen cyanide to isocyanic acid which comprises passing a gas feed stream of hydrogen cyanide, oxygen and inert gas under adiabatic conditions in contact with a solid catalyst effective to promote the reaction of hydrogen cyanide and oxygen to form isocyanic acid, the proportion of oxygen being at least one-half mole per mole of hydrogen cyanide, the reaction temperature at the catalyst being about 500 - 700°C, and said temperature being controlled by the proportion of inert gas in said gas feed stream.
2. The process according to Claim 1 in which the proportion of oxygen is between 0.5 to 0.7 moles per mole of hydrogen cyanide.
3. The process according to Claim 1 in which the inert gas is nitrogen.
4. The process according to Claim 3 in which the proportion of nitrogen is between 9 to 16 moles per mole of hydrogen cyanide.
5. The process according to Claim 1 in which the catalyst is silver.
6. The process according to Claim 5 in which the silver catalyst is in the form of crystals.
7. The process according to Claim 1 in which the contact time with the catalyst is on the order of 10 to 100 milliseconds.
8. The process according to Claim 1 in which the inert gas is nitrogen, the proportion of oxygen is from 0.5 to 0.7 moles per mole of hydrogen cyanide, the pro-portion of nitrogen is between 9 to 16 moles per mole of hydrogen cyanide, the catalyst is in the form of silver crystals, and the catalyst contact time is on the order of 10 to 100 milliseconds.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US305,057 | 1981-09-24 | ||
| US06/305,057 US4364913A (en) | 1981-09-24 | 1981-09-24 | HNCO Manufacture by adiabatic air oxidation of HCN |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1176429A true CA1176429A (en) | 1984-10-23 |
Family
ID=23179135
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000408075A Expired CA1176429A (en) | 1981-09-24 | 1982-07-26 | Hnco manufacture by adiabatic air oxidation of hcn |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US4364913A (en) |
| JP (1) | JPS5869719A (en) |
| CA (1) | CA1176429A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CH676361A5 (en) * | 1989-01-05 | 1991-01-15 | Lonza Ag | |
| US20080124532A1 (en) * | 2006-11-29 | 2008-05-29 | Basf Corporation | Materials and oligomers in low voc coatings |
| JP7304841B2 (en) * | 2020-09-11 | 2023-07-07 | 宇部マテリアルズ株式会社 | Method for producing isocyanic acid |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2712493A (en) * | 1953-03-17 | 1955-07-05 | Du Pont | Manufacture of cyanogen |
| GB883110A (en) * | 1957-05-15 | 1961-11-22 | Roehm & Hass G M B H | Oxidation of hydrogen cyanide |
| DE1079612B (en) * | 1959-01-24 | 1960-04-14 | Roehm & Haas Gmbh | Manufacture of dicyan |
| US4032620A (en) * | 1974-07-18 | 1977-06-28 | Mitsubishi Chemical Industries Ltd. | Process for preparing dicyan |
-
1981
- 1981-09-24 US US06/305,057 patent/US4364913A/en not_active Expired - Fee Related
-
1982
- 1982-07-26 CA CA000408075A patent/CA1176429A/en not_active Expired
- 1982-09-20 JP JP57162449A patent/JPS5869719A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPH024529B2 (en) | 1990-01-29 |
| US4364913A (en) | 1982-12-21 |
| JPS5869719A (en) | 1983-04-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0217532B1 (en) | Catalytic hydrogen generator for use with methanol | |
| US5334751A (en) | Ethyl acetate from ethanol | |
| KR900002545B1 (en) | Method for production of chlorine from hydrogen chloride | |
| CA2243872C (en) | High purity oxygen for ethylene oxide production | |
| CA2353052C (en) | Hydrogen cyanide synthesis process | |
| US5871705A (en) | Process for producing trichlorosilane | |
| EP0010902B1 (en) | Process for the production of (meth)acrylic acid by the catalytic vapour phase oxidation of isobutane or propane | |
| US4603207A (en) | Conversion of a mixture of 3-methylpyridine and 3-methylpiperidine to 3-cyanopyridine | |
| EP0567273A1 (en) | Improved process for ethylene epoxidation | |
| US2076953A (en) | Manufacture of hydrocyanic acid | |
| CA1176429A (en) | Hnco manufacture by adiabatic air oxidation of hcn | |
| US4449006A (en) | Preparation of methyl mercaptan from carbon oxides | |
| US2083824A (en) | Manufacture of hydrocyanic acid | |
| US4415499A (en) | Process for the manufacture of palladium(II) catalyst and for the manufacture of alkenyl esters of carboxylic acids employing said catalyst | |
| US4205181A (en) | Process for preparing unsaturated esters | |
| US3023226A (en) | Process for the preparation of acrylonitrile from propylene and nitric oxide | |
| JP3681503B2 (en) | Process for the production of difluoromethane | |
| US3310559A (en) | Process for the catalytic production of melamine from gaseous cyanic acid | |
| EP0075675B1 (en) | Hnco manufacture by catalytic oxidation of hcn with a pd doped ag catalyst | |
| US4876348A (en) | Process for making 3-cyanopyridine | |
| US4536492A (en) | Catalyst for the preparation of methyl mercaptan from carbon oxides | |
| US4869889A (en) | Process for the production of hydrogen cyanide | |
| CA1171842A (en) | Hnco manufacture by catalytic oxidation of hcn with a pd doped ag catalyst | |
| US3944656A (en) | Process for the production of cyanogen chloride | |
| US2861870A (en) | Manufacture of hydrogen cyanide |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEC | Expiry (correction) | ||
| MKEX | Expiry |